Using Port 1

[TDEdwards]

Two questions on the use of port 1 on a NMIY0031 card.<p>The documentation on the NMIY0031 states<p>&quot;J5 gives the user access to Port 1 of the processor, timers 0 and 1, and interrupts 0 and 1.&quot;<br> <br>Now I can see from the J5 pinout diagram that the timers can be accessed on pins 19 (T0) and 20(T1). But I can't work out which pins can be used for Interrupt 0 and Interrupt 1? <p>Also, the documentation states <p>&quot;Caution: be certain that any load/source attached meets the specifications of the 8031 processor.&quot; Can you give me some guidelines here please? <p>Thanks in advance<p>Trefor Edwards<br>

[nmitech]

Sorry, on the document page 22 was missing pin 17 & 18. The missing pinouts should be Pin 17 (INT0) and pin 18 (INT1). You should be able to see the labels on the PCB very clearly and it locates next to T0 and T1 respectively. In case if you can see the labels on your board, you can also double check on the silkscreen sheet that provided with the nmiy-0031.<p>Per 8051 Specs, PORT1: <br>Vol: 1.6mA. <br>Voh: -80 uA.<p>As you can see it may have enough current to drive some low power input devices; but it is not enough for source/sink the LED power for example. In most cases, you need to have some kind of buffers or amplifier to drive a led or other devices.<br>